Basma Aiouche ( Cl 214) is an Arts et Metiers and MIT alumna. 

Here is her Monday Advice #3 to A&M students (enrolled in "parcours US" program):

You will need 3 recommendation letters for each application to American Universities. In all letters, a person who will recommend you, will need to mention the program and the university you’re applying to. All the letters should be customized and not repetitive. Please spend some time with a person who agreed to recommend you to discuss the content of the letter.

Basma Aiouche's full Louis Magne report is available on our website (you need to sign up first):